Potential Risks of Cannabis Use in People with Type 1

Study assesses the prevalence of complications following regular use of cannabis.

The use of cannabis is becoming increasingly common as the number of states in the Union decriminalize it. Consequently, it is becoming increasingly important to understand how cannabis use affects specific disease states, and if its use will alter patient care. This task is made more difficult when faced with the large amount of health claims that have been made about cannabis use. With regards to diabetes, a recent study suggests that there is a correlation between cannabis use and improved beta cell function and insulin sensitivity. Conversely, a recent JAMA case series highlighted a potentially increased occurrence rate of diabetic ketoacidosis (DKA) in people with type 1 who regularly use cannabis. In an effort to demystify at least one aspect of cannabis use, this study aims to evaluate the comparative occurrence rate of DKA in people with type 1 diabetes who do and do not use cannabis.

As this study aims only to determine a correlational relationship, a retrospective cohort study design was selected. The primary outcome of the study was the occurrence of DKA requiring hospitalization. Patients were considered for participation if they were at least 18 years of age with type 1 diabetes and being treated at the Barbara Davis Center for Diabetes in Colorado. The Barbara Davis Center was an ideal setting for this study due to the fact that use of cannabis is legal for both recreational and medical purposes in Colorado. Patients were deemed ineligible if they were pregnant or had a type of diabetes other than type 1. A one time, in-person questionnaire was used to collect diabetes and cannabis use history for the previous 12 months. Analysis of continuous data was performed via t-test and categorical data was assessed via x2 test.

In all, there were 631 eligible patients identified at the Barbara Davis Center for Diabetes. All were sent invitations to participate in the study; however, only 450 responded. Of the 450 who agreed to participate, 29.8% (134 individuals) reported cannabis use within the previous 12 months. Participants who reported recent use of cannabis were on average younger (31.3 compared to 39.1 years of age), had a shorter duration of diabetes, and had a lower education and income level. In an effort to correct for the discrepancy in group size and other baseline characteristic variability, cannabis non-users were matched with the cannabis user group based on baseline criteria in order to make a group of equal size and equivalent characteristics. With regards to the primary outcome, those who reported use of cannabis within the past 12 months exhibited a higher incidence of hospitalizations due to DKA compared to the variable matched comparator group (22 vs 8 cases respectively). The data did not seem to indicate any significant differences in severe hypoglycemia between groups.

As cannabis use becomes more broadly decriminalized, it is becoming increasingly necessary for physicians to consider its effects on their patients. Despite the purported health benefits of cannabis, its use may produce deleterious effects that complicate patient care. With regards to type 1 diabetes, the results of this study suggest that regular use of cannabis is correlated with an increased risk of hospitalization due to DKA. At the very least, this evidence should prompt clinicians caring for patients who have type 1 to question cannabis use and to counsel them on it. However, in addition to that, these results should stimulate further study of other potential medication or disease state interactions involved with the use of cannabis.

Practice Pearls:

Cannabis use is becoming increasingly prevalent in the United States as more and more states shift toward decriminalization of medical and/or recreational use.

Cannabis use is correlated with increased incidence of hospitalizations due to DKA.

Patients with type 1 should be counseled on the potential risk of regular cannabis use.